George Clooney may never be confused for a Mensa candidate, but the “trophy husband” can hike his IQ simply by hanging out with his brainy wife, a new study suggests.

Clooney, who tied the knot with beautiful human-rights lawyer Amal Alamuddin in Venice in 2014, has joked that the only way he can win an argument with the stunner is by “arm-wrestling her.”

But the actor might be getting smarter by the day.

That’s because the best way to boost your bean is to “marry someone smarter than yourself, find an intellectually challenging job and hang out with bright friends,” leading psychologist James Flynn told the Sunday Times of London.

“Any of these things could raise your own intelligence,” said Flynn, noting that intelligence, long thought to become fixed at about age 18, can grow throughout adulthood by 10 IQ points or more.

“Intelligence has always been thought to be static,” said Flynn, the author of the upcoming book, “Does Your Family Make You Smarter?”

“However, the new evidence shows that this is wrong,” he said.

“The brain seems to be rather like a muscle — the more you use it, the stronger it gets. That means you can upgrade your own intelligence all through life.”

The New Zealand professor revealed that even light-hearted banter at home can boost IQ by several points.